Tree Bark+ adds bark for all Vanilla Trees, so you can re-apply it later. Bark can be used as a simple/short fuel-source for the furnace.
Q/A
How to get Bark?
You get Bark by stripping a Tree.
What do I do with Bark?
You can right click a stripped log with bark and the log gets its bark back.
Deobfuscated Versions / Source Code:
Deobfuscated files before v3.0, everything after is on github. 1.19 1.18 1.17 1.16
Showcase :
Thanks Pravculear